How did Humans not survive the rising levels?(The smart ones, anyway)
It's not just those that killed off terrestrial (as opposed to aquatic) life. Yes, those lead to huge reductions in landmasses and therefore stark overpopulation in remaining areas, but more importantly, huge shortages both in food and water (if it's all salt water, where are we going to get the energy needed to distil it all?). I believe that there was a significant shift in global temperatures and/or the atmospheric composition, a strong piece of evidence being one of my favourite Squid Sisters stage announcement lines: roughly, "Apparently, vegetables didn't exist when Grandpa was our age!". You know why? Because the technology required to culture them (in Kelp Dome and similar locations) wasn't developed until very recently in the Splatoon universe.
Very few remnants of many food staple plants we know today stayed around after the downfall of humanity (the big apocalypse dome thingy in Denmark could be where a lot of them were recovered from, actually). That's very strong evidence to the fact that conditions changed so drastically that land mammals just weren't able to live any more, regardless of medical technology (even if it existed, it couldn't possibly support such a huge number of humans. Eventually, the last energy and/or drug reserves required for such lifespan-elongating treatments must have run out, as they naturally would if the primary sector were as devastated as it's likely to be if climate change continues. It's very much the first one to get hit), as if the planet were changed to a temperate Martian wasteland.
Inkling civilisation can't have existed for incredibly long; I think that after the effective end of climate-damaging life, the atmosphere
was gradually able to regulate itself to the point that the prior-dwindling numbers of birds, bugs, etc. were able to recover their own populations to be suitable to the remaining amount of land. We still see loads of other plants growing naturally in the world of Splatoon. Such grasses, weeds and flowers are much better-suited to rapid natural selection and adaptation, so they lived on through the climate catastrophe unaided.
But invertebrate life, after claiming the land (there must have been some strong evolutionary advantage to leaving the seas. I suspect that oceanic pollution was severe to an extent that a sufficient amount of natural selection was forced to occur to create breeding populations of pseudo-Inklings, etc.. It's much harder for the seas to clean themselves naturally than for the atmosphere to re-balance, to be sure), eventually would make the mistake of locating and re-purposing human technology. Why was there a Great Turf War? Rising sea levels.
The great climate catastrophe was set to re-occur, and I believe that the unsung heroes of recent history (that is, within a century of the game's setting) were those who realised the most severe problem that had to be prevented. Splatoon features wind turbines, ink referred to as good for the environment, cutting down on online shopping... I believe, or want to believe, that the world of the game that we play shows us how terribly wrong the present development of our civilisation is slated to turn, and how simply it all could be bettered, even if it took a global conflict to bring the second wave to their senses.
How do inklings get from inkopolis tower to the battle stages so quickly?
... Super Jumping, I guess.
Why do Inklings have cars if they can Super Jump? Or do the cars just belong to other races?
